Wavelet taui: whakatau tauira tono

Kua auraa te taeraa mai o kāmera mamati ngāwari e te wahi nui o nga tangata o te ao, ahakoa o tau me te ira, kua riro te peu ki te hopu i tona nga taahiraa me hoatu o ratou whakapakoko i runga i whakaatu tūmatanui i roto i te whatunga pāpori. I tua atu, ki te whakanohoia mua te pūranga whakaahua whānau i roto i te album taua, i tenei ra ngā reira o rau o ngā pikitia. I roto i te tikanga ki te whakahaere i rokiroki me te tuku puta noa whatunga rapu i te whakapakoko mamati o whakaiti taimaha. Ki tenei mutunga, e whakamahia tikanga e kua hāngai i runga i ngā hātepe, tae atu i te wavelet taui. He aha te mea te reira, korero to tatou tuhinga.

He aha te he whakapakoko mamati

kanohi mōhiohio Visual i roto i te rorohiko i roto i te puka o tau. I roto i ngā faingofua, he whakaahua i tangohia ki te pūrere mamati, ko te tepu i nei te pūtau e tomo te uara o ia o tona kara pika. A, no te haere mai te reira ki te whakapakoko taetahi, ka e whakakapi ratou e uara luminance i te wā [0, 1], i reira 0 whakamahia te ki kōrero ki pango, me 1 - ma. E hoatu Ētahi atu ngā tae tau hautanga, engari ki a ratou tuke ki te whakahaere, na atu te whānui kei te me te uara tīpakohia i te wā i waenganui i te 0 me te 255. He aha te mea tenei? E mea ohie! Ki tenei kōwhiringa i roto i te kanohi pūtakerua mō te whakawaehere te luminance o ia pika titau rite kotahi paita. E mea papû e hiahiatia te rota o te mahara te ki te rokiroki ara he whakapakoko iti. Hei tauira, te rahi pikitia o 256 x 256 pika e 8 KPaita.

He kupu ruarua e pā ana ki ngā tikanga image kōpeketanga

He pono kua kite katoa te kounga rawakore o te pikitia te wahi i reira he distortions i te puka o tapawhā o te taua tae, e te hunga kua huaina tao'ao. whakatika ratou rite ki te hua o te kōpeketanga rōhi pera-ka karanga. Ka taea e tino whakaiti te reira i te taimaha o te whakapakoko, Heoi, ka pānga te taniwha, i te reira i runga i tona kounga.

Hoki rōhi hātepe kōpeketanga ngā:

• JPEG. Ko tenei i tawhiti tetahi o nga hātepe tino rongonui. Kei te hāngai te reira i runga i te whakamahi o te whenu motuhake taui. I roto i te tika kia tuhia te reira e reira he kōwhiringa mō te JPEG Ngarokore mahinga kōpeketanga. Ko ētahi o ēnei Ngarokore JPEG me JPEG-LS.
• JPEG 2000. whakamahia te hātepe kei te i runga i ngä tüäpapa pūkoro, ka hāngai ki runga ki te tono o te wavelet motuhake taui.
• kōpeketanga rauponga. I roto i ētahi wā, ka taea te reira ki a koutou te whiwhi whakapakoko o te kounga pai noa ki te kōpeketanga kaha. Heoi, e tika ana ki ngā raruraru ki te patenting o tenei tikanga tonu ki te kia tāwāhi.

hātepe kōpeketanga Ngarokore whakamana e:

• RLE (whakamahia rite te tikanga tuatahi i roto i te hōputu TIFF, BMP, TGA).
• LZW (whakamahia i roto i te hōputu GIF).
• LZ-Huffman (whakamahia hoki hōputu teitei).

Fourier taui i

I mua i tahuri ki te wavelet, hanga ana e ia tikanga ki te tūhura i te mahi e pā ana, whakaahua i te whakarea o te roha o te mōhiohio tuatahi ki wāhanga māmā, ie. E. Harmonic wiri ki iarere rerekē. I roto i te mau parau te tahi atu, te Fourier taui - he taputapu ahurei honotanga ao motuhake, me te tonu.

rite tenei titiro reira:

tuhituhia te tātai koaro te rite e whai ake nei:

He aha te mea he wavelet

Muri i tenei ingoa huna te mahi pāngarau, e taea ai e koe te tātari i te wāhanga auau rerekē o te raraunga whakamātautau. Ko tōna kauwhata Ko te undulation nei kaha tīwera heke ki te 0 atu i te takenga. I roto i te moni whānui e takoto nga tau whakarea wavelet tohu wāhi.

He rerekē i tūāwhiorangi Fourier tikanga spectrograms Wavelet, mai i ngā āhuatanga e pā ana tohu tūāwhiorangi ki ratou wāhanga pae tino.

huringa Wavelet

Tenei tikanga o te faafariuraa tohu (mahi) ka taea ki te iriti i te reira i te wa i roto i te kanohi wa-auau.

Hei wavelet i taea huringa, mo te mahi e hāngai ana wavelet, me tutaki te tikanga e whai ake nei:

• Ki te hoki etahi ψ mahi (t) -Fourier taui e te puka

Me kia makona taua huru:

I tua atu:

• Me whai Wavelet he pūngao fakataimí;
• kia waiho reira integrable tonu, me te whai tautoko kiato;
• Me paetata wavelet e rua i roto i te auautanga me i te wa (wāhi).

momo

He wavelet tonu taui te whakamahia hoki te tohu tēnā. He nui atu ngā Ko tona orotahi motuhake. I muri i te katoa, ka taea te whakamahi i te reira no te tukatuka mōhiohio i roto i rorohiko. Heoi, whakatika te raruraru i roto i e kore e taea te whiwhi te tātai mō te fiberboard motuhake e tātai discretization DNP tika ohie.

I kitea te otinga ki tenei raruraru i Daubechies, ko wai i taea e ki te whiriwhiri i te tikanga ki te hanga i te raupapa o wavelets poutū, ia o nei tautuhia e te maha fakataimí o tau whakarea. I muri mai i hanga hātepe nohopuku, pērā i te hātepe Malla. I roto i tona tono ki te hanehane ranei ki te whakahoki mai i te tikanga e hiahiatia ana ki te mahi i ngā mahi CN, te wahi N - tauira roa, a ki - te maha o tau whakarea.

Vayvlet haar

Hei kōpeke he whakapakoko, he mea e tika ana ki te kitea tetahi auautanga roto ona raraunga, a tae noa pai ki te ka waiho reira roa mekameka o ngā kore. Ko tenei wahi e taea e te mea whai hua ki te wavelet taui hātepe. Heoi, haere tonu tatou ki te arotake i te tikanga mahi i roto i te raupapa.

Tuatahi ko reira e tika ana ki te haamana'o e whakapakoko te wherikotanga o pika pātata te nuinga o te wā āhuatanga e te nui iti. Ahakoa, ki te reira he whakaahua i runga i ngā pae tūturu ki koi, rerekē ngā rerekētanga o wherikotanga, noho ratou he anake wahi iti o te whakapakoko. Ka rite ki te tauira, te tango i runga i te whakamātautau mohiotia Lenna image kiwikiwi. Ki te tangohia e tatou i te kopu o te luminance o ona pika, na ka puta te wahi o te raina tuatahi rite te raupapa o ngā tau 154, 155, 156, 157, 157, 157, 158, 156.

Ka taea e koe te tono i te tikanga raorao pera-ka karanga ki te tiki ngā kore ki reira. Ki te mahi i tenei, kia mau te tau tuatahi anake, a mo nga ētahi atu tango nga rerekētanga anake o ia o te tetahi o mua ki te tohu "+" ranei "-".

Ko te hua ko te raupapa 154,1,1,1,0,0,1, -2.

He ngoikoretanga o te raorao-whakawaehere ko tona wahi-kore. I roto i te mau parau te tahi atu, e kore e taea ki te tango i te wāhanga anake o te raupapa, me te kitea i roto i te mea tiahotanga kua whakawaeheretia reira, decoded, ki te kahore katoa o te uara i roto i te mua o ia ia.

Hei hinga tenei ngoikoretanga, kua wehea te maha ki takirua me ko te hawhe te moni o (v. A) me te hawhe te rerekētanga (v. D), m. F. hoki (154,155) (156,157) (157,157) (158,156) i (154.5 ia, 0.5) (156.5,0.5) (157,0.0), (157, -1.0). I roto i tenei take, ko reira taea tonu ki te kitea te uara o nga tau e rua i roto i te rua.

I roto i te whānui, e taui i te wavelet motuhake o te S tohu, to tatou:

E whai ana tēnei tikanga i te take motuhake o te wavelet tonu taui, haar me whānui e whakamahia ana i roto i mara ngā o te tukatuka raraunga me te kōpeketanga.

kōpeketanga

Ka rite ki kua whakahuatia, tetahi o nga tono o te wavelet whakaahua ke hātepe ko te tikanga kōpeketanga JPEG 2000 te whakamahi i haar i runga i te pere translation o rua pika i roto i te X me Y pere (X + Y) / 2 me (X - Y) / 2. Ko reira rawaka ki tini te pere tuatahi i roto i te kopu i raro.

Ki te nga ngā ake, tangohia atu kopu, e kua whakaritea i runga i te H. kopu hauroki reira, tukatuka te vector tuatahi motuhake o tona roa i roto i takirua.

whiriwhiringa

Ko te hua "hawhe-moni" - ko te uara luminance toharite o pika i roto i takirua. Ko te uara ka tahuri ki te whakapakoko e hoatu ki a ia he tārua, iti i roto i te 2 nga wa. I roto i Pine tenei hawhe-moni wherikotanga, t. E. "Tātari" i pakū matapōkere o ratou uara, me te mahi kia rite ki whiriwhiringa auau.

Na kia mahi a ki te hunga e whakaatu te rerekētanga. Kei te "taratahi" ratou interpixel "pakū", te tango i te wāhanga tamau, ie. E. "Tātari" uara i iarere iti.

Ahakoa i te runga ake haar wavelet whakaahua ke hoki te "horoi" riro te reira kitea ai ko reira he rua o whiriwhiringa e wehe he tohu ki e rua ngā wāhanga: te auau tiketike, me te auau iti. noa anō-tahoê enei āhuatanga ki te whiwhi i te tohu taketake.

tauira

Pea hiahia tatou ki te kōpeke te whakaahua (image whakamātautau Lenna). A feruri i te hi'oraa o te wavelet whakaahua ke i te kopu o brightnesses pika. Ko te wāhanga nui-auau o te whakapakoko, ko te kawenga mō te whakaatu taipitopito pai, me te whakamārama ana i te reo. Ko te iti-auau, kei reira ngā kōrero e pā ana ki te āhua o te mata, me te rōnaki maeneene o te wherikotanga.

He taua Āhuatanga whakaahua o te perception tangata e te muri, ko te wae nui atu. tikanga o tēnei e ka kōpeke taea te maka he tetahi wahi o nga raraunga tiketike-auau. Ko te atu na te mea kua reira iti uara me te whakawaeheretia atu compactly.

Hei whakanui i te tohu o te kōpeketanga taea te tono e rave rahi taime haar panoni ki te raraunga iti-auau.

Ko te whakamahi o ngā huānga e rua-ahu

Ka rite ki kua whakahuatia, te whakapakoko mamati i roto i te rorohiko kei roto i te puka o te kopu o te hohonuraa uara o ona pika. Ko te kupu, kia waiho tatou hiahia i roto i te haar rua-ahu wavelet taui. Hei whakatinana i te mea e tika noa ki te mahi i tona faafariuraa ahu hoki ia rarangi me ia tīwae o te kopu o nga hohonuraa o pika i roto i te whakapakoko.

Uara tata ki te kore, ka taea te maka, kahore tino kino ki te whakapakoko decoded. mohiotia ana tēnei tukanga te rite quantization. A i tenei wā o te mōhiohio ngaro te. E te ara, kia huri i te maha o ngā āhuatanga nullable, reira huri te tohu o te kōpeketanga.

hua enei kaupae katoa i taua whiwhi te kopu e nei kei nui moni o 0. kia tuhituhi aho i aho i roto i te kōnae kuputuhi me te kōpeke tetahi pūranga.

wetewaehere

Te huringa kōaro i roto i te whakapakoko i runga i te hātepe e whai ake nei:

• unpacks te reira i te pūranga;
• pā kōaro haar taui;
• Kei te tahuri te whakapakoko decoded ki te kopu.

Painga whakaritea ki JPEG

было сказано, что он основан на ДКП. A, no te whakaaro i te hātepe korerotia Ngātahi Tohunga Photographic Group i e te hāngai ki runga ki DCT. kawea ana tēnei faafariuraa i roto i roto i poraka (8 x 8 pika). Ka rite ki te hua, ki te te kōpeketanga kaha i runga i te ahua iti riro hanganga poraka appreciable. I roto i kōpeketanga whakamahi wavelets he raruraru taua he ngaro. Heoi, kia puta haruru momo rerekē e whai i te ahua o ngā kare a tawhio noa tapa. Kei te whakapono te reira e mau tao'ao rite i runga i toharite iti kitea atu "tapawhā" e e hanga, no te whakamahi i JPEG hātepe.

Na e matau ana koutou he aha wavelets he aha e ratou a he aha mahi whakamahi hoki ratou i kitea i roto i te mara o te tukatuka, me te kōpeke whakapakoko mamati.